WELLINGTON, Colo. -- Authorities have made an arrest in the case of a 14-year-old teen who was sexually assaulted by a man who used a spare key to get inside her house.

The Larimer County Sheriff's Department said Benjamin William Vivian, 24, was arrested after DNA tests connected him to the crime. Vivian lives in the same Larimer County community of 3,000 residents.

The sexual assault occurred at 3 a.m., on Sept. 18 in the 3700 block of Box Elder Court, according to the sheriff's office.

The girl had told her mother that she was going to spend the night at a friend's house but changed her mind and went home instead. The teen told investigators she awoke to find a bald man next to her bed and that he raped her while holding a pillow over her face. Later she called 911 and ran to a neighbor's house.

The teen's grandmother believes that the man watched the girl get into the house -- using the spare key she had hidden near the front door -- and he used the same key to slip into the house unnoticed.

Investigators said Vivian had connections to the family, having worked for the victim's mother and had been to the home where the assault occurred in the past. He works at a local bar in Wellington.

Vivian is being held without bond.

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